Firearm receiver pins for quick disassembly and assembly

Abstract

An apparatus implementable on a firearm may include a takedown pin and a pivot pin. The takedown pin holds together a rear portion of lower and upper receivers of the firearm. The pivot pin holds together a front portion of lower and upper receivers of the firearm. Each of the takedown pin and pivot pin respectively includes a head and a generally cylindrical shank extending from the head toward a distal end thereof opposite the head. The shank is configured with: (1) a first groove track extending along a longitudinal axis of the shank, (2) a second groove track parallel to the first groove track and extending along the longitudinal axis of the shank, and (3) a linking groove track extending around the longitudinal axis of the shank and linking the first groove track and the second groove track.

What is claimed is: 
     
       1. An apparatus implementable on a firearm, comprising:
 a pin configured to hold together a lower receiver of the firearm and an upper receiver of the firearm, the pin comprising:
 a head; and 
 a generally cylindrical shank extending from the head toward a distal end of the takedown pin opposite the head, the shank configured with:
 a first groove track extending along a longitudinal axis of the shank; 
 a second groove track shorter than the first groove track and extending along the longitudinal axis of the shank; and 
 a linking groove track extending around the longitudinal axis of the shank and linking the first groove track and the second groove track, 
 
 
 wherein the linking groove track links a distal end of the second groove track and a midpoint between a first distal end of the first groove track and a second distal end of the first groove track opposite the first distal end thereof. 
 
     
     
       2. The apparatus of  claim 1 , wherein:
 the first groove track, the second groove track and the linking groove track are configured to receive a tip portion of a detent pin of the firearm, 
 when the tip portion of the detent pin is received in the first groove track, the first groove track limits the takedown pin to move linearly along the longitudinal axis of the takedown pin, 
 when the tip portion of the detent pin is received in the linking groove track, the linking groove track limits the takedown pin to rotate partially around the longitudinal axis of the takedown pin to allow the tip portion of the detent pin to move along the linking groove track between the first groove track and the second groove track, and 
 when the tip portion of the detent pin is received in the second groove track, the second groove track limits the takedown pin to move linearly along the longitudinal axis of the takedown pin. 
 
     
     
       3. The apparatus of  claim 2 , wherein:
 two distal ends of the first groove track are close-ended such that, when the tip portion of the detent pin is received in the first groove track, the detent pin prevents removal of the takedown pin from the firearm, 
 the linking groove track connects to a middle portion of the first groove track between the two distal ends of the first groove track such that, when the tip portion of the detent pin moves from the linking groove track to the first groove track, the tip portion of the detent pin is allowed to move between the two distal ends of the first groove track by linear motions of the takedown pin, 
 the second groove track extends between the linking groove track and the distal end of the takedown pin, 
 a first distal end of the second groove track connects with the linking groove track, and 
 a second distal end of the second groove track opposite the first distal end is open-ended such that, when the tip portion of the detent pin is received in the second groove track, the takedown pin is removable from the firearm by a linear movement of the takedown pin with the tip portion of the detent pin sliding out of the second distal end of the second groove track. 
 
     
     
       4. The apparatus of  claim 3 , wherein at least a portion of a bottom surface of the second groove track comprises a slope such that a depth of a first end of the slope toward the first distal end of the second groove track is greater than a depth of a second end of the slope toward the second distal end of the second groove track. 
     
     
       5. The apparatus of  claim 3 , wherein the shank further comprises:
 a first recess at an intersection between the first groove track and the linking groove track; and 
 a second recess at an intersection between the second groove track and the linking groove track, 
 wherein the first recess and the second recess permit the takedown pin to click and stop when the takedown pin is rotated to allow the tip portion of the detent pin to move in the linking groove track from the first groove track to the second groove track or from the second groove track to the first groove track. 
 
     
     
       6. The apparatus of  claim 5 , wherein the shank further comprises:
 a third recess at one of the two distal ends of the first groove track; and 
 a fourth recess at another of the two distal ends of the first groove track, 
 wherein the third recess and the fourth recess permit the takedown pin to click and stop when the takedown pin is moved linearly to allow the tip portion of the detent pin to move in the first groove track between the two distal ends of the first groove track. 
 
     
     
       7. The apparatus of  claim 1 , wherein a circumference of the head of the takedown pin comprises textures, and wherein the textures comprise a plurality of grooves around the circumference, dots, diagonal lines, golf ball patterns, hexagonal patterns, non-smooth patterns, or a combination thereof. 
     
     
       8. The apparatus of  claim 1 , wherein the pin comprises a takedown pin configured to hold together a rear portion of the lower receiver of the firearm and a rear portion of the upper receiver of the firearm. 
     
     
       9. The apparatus of  claim 1 , wherein the pin comprises a pivot pin configured to hold together a front portion of the lower receiver of the firearm and a front portion of the upper receiver of the firearm. 
     
     
       10. An apparatus implementable on a firearm, comprising:
 a lower receiver of the firearm; 
 an upper receiver of the firearm; and 
 a pin configured to hold together the lower receiver and the upper receiver, the pin comprising:
 a head; and 
 a generally cylindrical shank extending from the head toward a distal end of the takedown pin opposite the head, the shank configured with:
 a first groove track extending along a longitudinal axis of the shank; 
 a second groove track shorter than the first groove track and extending along the longitudinal axis of the shank; and 
 a linking groove track extending around the longitudinal axis of the shank and linking the first groove track and the second groove track, 
 
 
 wherein the linking groove track links a distal end of the second groove track and a midpoint between a first distal end of the first groove track and a second distal end of the first groove track opposite the first distal end thereof. 
 
     
     
       11. The apparatus of  claim 10 , wherein:
 the first groove track, the second groove track and the linking groove track are configured to receive a tip portion of a detent pin of the firearm, 
 when the tip portion of the detent pin is received in the first groove track, the first groove track limits the takedown pin to move linearly along the longitudinal axis of the takedown pin, 
 when the tip portion of the detent pin is received in the linking groove track, the linking groove track limits the takedown pin to rotate partially around the longitudinal axis of the takedown pin to allow the tip portion of the detent pin to move along the linking groove track between the first groove track and the second groove track, and 
 when the tip portion of the detent pin is received in the second groove track, the second groove track limits the takedown pin to move linearly along the longitudinal axis of the takedown pin. 
 
     
     
       12. The apparatus of  claim 11 , wherein:
 two distal ends of the first groove track are close-ended such that, when the tip portion of the detent pin is received in the first groove track, the detent pin prevents removal of the takedown pin from the firearm, 
 the linking groove track connects to a middle portion of the first groove track between the two distal ends of the first groove track such that, when the tip portion of the detent pin moves from the linking groove track to the first groove track, the tip portion of the detent pin is allowed to move between the two distal ends of the first groove track by linear motions of the takedown pin, 
 the second groove track extends between the linking groove track and the distal end of the takedown pin, 
 a first distal end of the second groove track connects with the linking groove track, and 
 a second distal end of the second groove track opposite the first distal end is open-ended such that, when the tip portion of the detent pin is received in the second groove track, the takedown pin is removable from the firearm by a linear movement of the takedown pin with the tip portion of the detent pin sliding out of the second distal end of the second groove track. 
 
     
     
       13. The apparatus of  claim 12 , wherein at least a portion of a bottom surface of the second groove track comprises a slope such that a depth of a first end of the slope toward the first distal end of the second groove track is greater than a depth of a second end of the slope toward the second distal end of the second groove track. 
     
     
       14. The apparatus of  claim 12 , wherein the shank further comprises:
 a first recess at an intersection between the first groove track and the linking groove track; and 
 a second recess at an intersection between the second groove track and the linking groove track, 
 wherein the first recess and the second recess permit the takedown pin to click and stop when the takedown pin is rotated to allow the tip portion of the detent pin to move in the linking groove track from the first groove track to the second groove track or from the second groove track to the first groove track. 
 
     
     
       15. The apparatus of  claim 14 , wherein the shank further comprises:
 a third recess at one of the two distal ends of the first groove track; and 
 a fourth recess at another of the two distal ends of the first groove track, 
 wherein the third recess and the fourth recess permit the takedown pin to click and stop when the takedown pin is moved linearly to allow the tip portion of the detent pin to move in the first groove track between the two distal ends of the first groove track. 
 
     
     
       16. The apparatus of  claim 10 , wherein a circumference of the head of the takedown pin comprises textures, and wherein the textures comprise a plurality of grooves around the circumference, dots, diagonal lines, golf ball patterns, hexagonal patterns, non-smooth patterns, or a combination thereof. 
     
     
       17. The apparatus of  claim 10 , wherein the pin comprises a takedown pin configured to hold together a rear portion of the lower receiver of the firearm and a rear portion of the upper receiver of the firearm. 
     
     
       18. The apparatus of  claim 10 , wherein the pin comprises a pivot pin configured to hold together a front portion of the lower receiver of the firearm and a front portion of the upper receiver of the firearm.